1. Field
Embodiments of the invention relate to the field of digital camera modules; and more specifically, to structures for setting the initial focus position during factory assembly.
2. Background
Many portable electronic devices, such as mobile cellular telephones, include a digital camera. The lenses for such cameras must be compact to fit within the case of the portable electronic device. At the same time there is a desire to provide an increasingly high quality camera function in these devices. To provide a higher quality image, some cameras found in portable electronic devices provide an autofocus feature and/or an adjustable iris to control exposure.
An image sensor, lens, and actuators for the lens are typically assembled into a camera module. The lens may be mounted in a actuator that moves the lens along its optical axis to change the distance between the lens and the image sensor. This changes the focal distance of the camera and allows a sharper image to be obtained for subjects over a greater range of distances from the camera. One such lens moving mechanism for moving a lens is a voice coil motor. Voice coil motors are relatively complex assemblies with a number of parts. Voice coil motors also consume a significant amount of power. The addition of an adjustable iris further increases mechanical complexity and power consumption in the camera module.
It would be desirable to provide a camera module that provides a focus actuator and adjustable iris with a structure that reduces mechanical complexity and power consumption.